#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>
#include<string.h>
#include<stdlib.h>
int isPalindrome(char* str)
{
	int len = strlen(str);
	int left = 0;
	int right = len - 1;
	while (left < right)
	{
		if (str[left] != str[right])
			return 0;
		left++;
		right--;
	}
	return 1;
}

int main()
{
	char* str = (char*)malloc(sizeof(char) * 100);
	scanf("%99[^\n]", str);
	if (isPalindrome(str))
	{
		printf("yes");
	}
	else {
		printf("no");
	}
	return 0;
}